8K Flashing Prompts Subroutine

To avoid screen flicker, I came up with this subroutine (at 200 in this example). The example program gives 6 flashing prompts. To change the number of flashes, change 6 in line 145. For different periods between flashes, change 3 in line 215. Run in SLOW mode.

 100 PRINT AT 21,6;"(0 TO 11)"
 105 PRINT AT 21,0;"INPUT"
 110 LET P=0
 115 GOSUB 200
 120 PRINT AT 21,0;"INPUT"
 125 GOSUB 200
 130 PRINT AT 21,0;"INPUT"
 135 GOSUB 200
 140 LET P=P+1
 145 IF P=6 THEN GOTO 155
 150 GOTO 120
 155 INPUT A$
 200 LET T=0
 205 LET T=T+1
 210 IF T=3 THEN RETURN
 215 GOTO 205
SYNTACTIC SUM: 19157, 8K